Improvement of body motion measurement using pressure data on Human Body Motion Interface

This research focuses on the electric wheelchair controlled by Human Body Motion Interface (HBMI). HBMI uses the body motion which is caused by the voluntary motion. From our previous research, it has been confirmed that HBMI, which uses the center of weight on the pressure sensor attached on the backrest has the ability of an interface. However the problem has also remained. The velocities of each wheel have determined based on the error between initial and current position of center of weight. The error increases in the proportion to the inclination of the body. In some cases, the error doesn´t increase due to the contact condition between body and backrest, even if the user leans own body. In this case, therefore, the user cannot control the wheelchair arbitrarily in spite of leaning his/her body. This paper shows the improvement to control wheelchair regardless of the amplitude of the error.